Copper metal, activated with one or more of the metals silver, platinum, palladium, manganese, cobalt, nickel, chromium and/or molybdenum on an alumina support, is well known as a catalyst for hydrogenation of acetylenes. Frevel et al. have issued several patents in which improved results are obtained (improved selectivity of hydrogenation of the acetylenic bonds in the presence of diolefinic bonding) by increasing the sodium content of the activated catalyst, U.S. Pat. No. 4,101,451, and/or high sodium oxide alumina, U.S. Pat. No. 3,912,789. However, these catalysts still hydrogenate some considerable amount of the diolefin components of such streams. As the diolefin content of these streams becomes more valuable it would be advantageous to reduce the hydrogenation of these diolefins (particularly butadiene) without also reducing the hydrogenation of the .alpha.-acetylenes.